The tutorial predominantly is about code. It's really just the one chapter on NetBeans. The rest of it is about Swing and can be done in any IDE.
I would not recommend working with a GUI builder, simply because as you say, you don't get to understand what's going on underneath. Start with simply windows and progressively work you way through adding GUI components and interacting with them. Understand the advantages of the MVC way of doing things.
And the best recommendation I can give is don't sit down to "Learn" Swing. Pick yourself out a project that interests you and you can do using Swing. By having a goal of a working program in mind, you will better absort the lessons that the tutorials give.
